5. Conclusions
Based on the result obtained in this study, the following main conclusions can be drawn:
chunky graphite formation is influenced by the inoculant chemical composition used in post-inoculation. It was found that the inoculant containing bismuth and rare earths prevents the chunky graphite formation and increases the nodule count;
the effect of bismuth in preventing chunky graphite formation was attribute to:
(a) its high resistance to fading
(b) its reaction with subversive elements;
(c) the formation of stable intermetallic compounds with rare earths which may act as heterogeneous nuclei for graphite nucleation;
• no thermal parameters were found to be correlated with chunky graphite precipitation;
• standard tensile tests showed the negative influence of chunky graphite on the ultimate tensile strength and the elongation to fracture.